统筹兼顾

反腐倡廉

New research raises new concerns that altering crops to withstand such threats may pose new risks from ______ the weeds themselves.

constitutional monarchy

Theoretical physicists use mathematics to describe certain aspects of Nature. Sir Isaac Newton was the first theoretical physicist, although in his own time his profession was called 'natural philosophy'. By Newton's era people had already used algebra and geometry to build marvelous works of architecture, including the great cathedrals of Europe, but algebra and geometry only describe things that are sitting still. In order to describe things that are moving or changing in some way, Newton invented calculus. The most puzzling and intriguing moving things visible to humans have always been the sun, the moon, the planets and the stars we can see in the night sky. Newton's new calculus, combined with his 'Laws of Motion', made a mathematical model for the force of gravity that not only described the observed motions of planets and stars in the night sky, but also of swinging weights and flying cannonballs in England. Today's theoretical physicists are often working on the boundaries of known mathematics, sometimes inventing new mathematics as they need it, like Newton did with calculus. Newton was both a theorist and an experimentalist. He spent many long hours, to the point of neglecting his health, observing the way Nature behaved so that he might describe it better. The socalled 'Newton's Laws of Motion' are not abstract laws that Nature is somehow forced to obey, but the observed behavior of Nature that is described in the language of mathematics. In Newton's time, theory and experiment went together. Today the functions of theory and observation are divided into two distinct communities in physics. Both experiments and theories are much more complex than back in Newton's time. Theorists are exploring areas of Nature in mathematics that technology so far does not allow us to observe in experiments. Many of the theoretical physicists who are alive today may not live to see how the real Nature compares with her mathematical description in their work. Today's theorists have to learn to live with ambiguity and uncertainty in their mission to describe Nature using math. In the 18th and 19th centuries, Newton's mathematical description of motion using calculus and his model for the gravitational force were extended very successfully to the emerging science and technology of electromagnetism. Calculus evolved into classical field theory. Once electromagnetic fields were thoroughly described using mathematics, many physicists felt that the field was finished, that there was nothing left to describe or explain. Then the electron was discovered, and particle physics was born. Through the mathematics of quantum mechanics and experimental observation, it was deduced that all known particles fell into one of two classes: bosons or fermions. Bosons are particles that transmit forces. Many bosons can occupy the same state at the same time. This is not true for fermions, only One fermion can occupy a given state at a given time, and this is why fermions are the particles that make up matter. This is why solids can't pass through one another, why we can't walk through walls—because of Pauli repulsion-the inability of fermions (matter) to share the same space the way bosons (forces) can. While particle physics was developing with quantum mechanics, increasing observational evidence indicated that light, as electromagnetic radiation, traveled at one fixed speed ( in a vacuum) in every direction, according to every observer. This discovery and the mathematics that Einstein developed to describe it and model it in his Special Theory of Relativity, when combined with the later development of quantum mechanics, gave birth to the rich subject of relativistic quantum field theory. Relativistic quantum field theory is the foundation of our present theoretical ability to describe the behavior of the subatomic particles physicists have been observing and studying in the latter half of the 20th century. But Einstein then extended his Special Theory of Relativity to encompass Newton's theory of gravitation, and the result, Einstein's General Theory of Relativity, brought the mathematics called differential geometry into physics. General relativity has had many observational successes that proved its worth as a description of Nature, but two of the predictions of this theory have staggered the public and scientific imaginations: the expanding Universe, and black holes. Both have been observed, and both encapsulate issues that, at least in the mathematics, brush up against the very nature of reality and existence. Relativistic quantum field theory has worked very well to describe the observed behaviors and properties of elementary particles. But the theory itself only works well when gravity is so weak that it can be neglected. Particle theory only works when we pretend gravity doesn't exist. General relativity has yielded a wealth of insight into the Universe, the orbits of planets, the evolution of stars and galaxies, the Big Bang and recently observed black holes and gravitational lenses. However, the theory itself only works when we pretend that the Universe is purely classical and that quantum mechanics is not needed in our description of Nature. String theory is believed to close this gap. Originally, string theory was proposed as an explanation for the observed relationship between mass and spin for certain particles called hadrons, which include the proton and neutron. Things didn't work out, though, and Quantum Chromodynamics eventually proved a better theory for hadtons. But particles in string theory arise as excitations of the string, and included in the excitations of a string in string theory is a particle with zero mass and two units of spin. If there were a good quantum theory of gravity, then the particle that would carry the gravitational force would have zero mass and two units of spin. This has been known by theoretical physicists for a long time. This theorized particle is called the graviton. This led early string theorists to propose that string theory be applied not as a theory of hadronic particles, but as a theory of quantum gravity, the unfulfilled fantasy of theoretical physics in the particle and gravity communities for decades. But it wasn't enough that there be a graviton predicted by string theory. One can add a graviton to quantum field theory by hand, but the calculations that are supposed to describe Nature become useless. This is because, as illustrated in the diagram above, particle interactions occur at a single point of spacetime, at zero distance between the interacting panicles. For gravitons, the mathematics behaves so badly at zero distance that the answers just don't make sense. In string theory, the strings collide over a small but finite distance, and the answers do make sense. This doesn't mean that string theory is not without its deficiencies. But the zero distance behavior is such that we can combine quantum mechanics and gravity, and we can talk sensibly about a string excitation that carries the gravitational force. This was a very great hurdle that was overcome for late 20th century physics, which is why so many young people are willing to learn the grueling complex and abstract mathematics that is necessary to study a quantum theory of interacting strings．

The majority of nurses are women, but in the higher ranks of the medical profession women are in a ______.

The exhibition's importance lies in its ______: curators have gathered a diverse array of significant works from many different museums.

FIT

Correction of the student's aberrant pronunciation is a continual, on-going process, not something reserved for lessons or exercises in pronunciation.

state visit

Oscar Wilde said he felt sorry for those who never got their heart's desire, but sorrier still for those who did. It seems to be a paradox. What's your understanding of it? Do you agree with him? Why or why not? You should write at least 400 words. You are required to support your ideas with relevant information and examples based on your own knowledge and experience.

好莱坞大片

The president explained that the purpose of taxation was to ______ government spending

When it was published in 1959, Robert Frank's book, The American, ______ hostility in the United States.

On the whole, books are less limited than ourselves. Often they sit on the shelves absorbing dust long after the writer has turned into a handful of dust—and it is precisely the appetite for this posthumous dimension that sets one's pen in motion. So as we toss and turn these rectangular objects in our hands we won't be terribly amiss if we surmise that we fondle, as it were, the urns with our returning ashes. After all, what goes into writing a book is, ultimately, a man's only life. Whoever said that to philosophize is an exercise in dying was right in more ways than one, for by writing a book nobody gets younger. Nor does one become any younger by reading one. Since this is so, our natural preference should be for good books. The paradox, however, lies in the fact that in literature 'good' is defined by its distinction from 'bad.' What's more, to write a good book, a writer must read a great deal of pulp—otherwise he won't be able to develop the necessary criteria. That's what may constitute bad literature's best defense at the Last Judgment. Since we are all moribund, and since reading books is time-consuming, we must devise a system that allows us a semblance of economy. Of course, there is no denying the pleasure of holding up with a fat, slow-moving, mediocre novel; but in the end, we read not for reading's sake hut to learn. Hence the need for the works that brings the human predicament into its sharpest possible focus. Hence, too, the need for some compass in the ocean of available printed matter.

Twitter

应试教育

She should be ______ and not make unreasonable demands.

Millions of elderly Germans received a notice from the Health Social Security Ministry earlier this month that struck a damaging blow to the welfare state. The statement informed them that their pensions were being cut. The reductions come as a stop-gap measure to control Germany's ballooning pension crisis. Not surprisingly, it was an unwelcome change for senior citizens such as Sabine Wetzel, a 67-year-old retired bank teller, who was told her state pension would be cut by $12.30, or 1% to $1,156.20 a month.'It was a real shock,' she says.'My pension had always gone up in the past.' There's more bad news on the way. On Mar. 11, Germany's lower house of Parliament passed a bill gradually cutting state pensions—which have been rising steadily since World War Ⅱ—from 53% of average wages now to 46% by 2020. And Germany is not alone. Governments across Western Europe are racing to curb pension benefits. In Italy, the government plans to raise the minimum retirement age from 57 to 60, while France will require that civil servants put in 40 years rather than 37.5 to qualify for a full pension. The reforms are coming despite tough opposition from unions, leftist politicians, and pensioners' groups. The explanation is simple: Europeans are living longer and having fewer children. By 2030 there will only be two workers per pensioner, compared with four in 2000. With fewer young workers paying into the system, cuts are being made to cover a growing shortfall. The gap between money coming in and payments going out could top $10 billion this year in Germany alone.'In the future, a state pension alone will no longer be enough to maintain the living standards employees had before they retired,' says German Health Social Security Minister Ulla Schmidt. Says Italian Finance Minister Giulio Tremonti: 'The welfare state is producing too few cradles and too few graves.' Of course, those population trends have been forecast for years. Some countries, such as Britain and the Netherlands, have responded by making individuals and their employers assume more of the responsibility for pensions. But many Continental governments dragged their feet. Now, the rapid runup in costs is finally forcing them to act. State-funded pension payments make up around 12% of gross domestic product in Germany and France and 15% in Italy—two percentage points more than 20 years ago. Pensions account for an average 21% of government spending across the European Union. The U.S. Social Security system, by contrast, consumes just 4.8% of GDP. The rising cost is having serious repercussions on key European nations' commitments to fiscal restraint.'Governments have no choice but to make pension reform a priority,' says Antonio Cabral, deputy director of the European Commission's Directorate General for Economic Financial Affairs. Just as worrisome is the toll being exacted on the private sector. Corporate contributions to state pension systems—which make up 19.5% of total gross pay in Germany—add to Europe's already bloated labor costs. That, in turn, blunts manufacturers' competitiveness and keeps unemployment rates high. According to the Institute of German Economics in Cologne, benefit costs reached a record 41.7% of gross wages in Germany last year, compared with 37.4% a decade before. French cement manufacturer Lafarge says pension cost of $121 million contributed to a 9% fall in operating profits last year. To cope, Germany and most of its EU partners are using tax breaks to encourage employees to put money into private pensions schemes. But even if private pensions become more popular, European governments will have to increase minimum retirement ages and reduce public pensions. While today's seniors complain about reduced benefits, the next generation of retirees may look back on their parents' pension checks with envy.

While this healthy lifestyle approach to health worked for some (the wealthy members of society), people experiencing poverty, unemployment or little control ______ the conditions of their daily lives benefited little from this approach.